1. Field of the Invention
The present invention generally relates to a sensing device and a reaction system, and more particularly, to a centrifugal force sensing device and a reaction system on centrifugal force.
2. Description of Related Art
In the prior art, a switch activated by centrifugal force is usually disposed in a rotating body, so that when the rotating body reaches a certain rotation speed to rotate, an action is activated. For example, in a device for automatically detecting tire pressure of a car fixed in the rim of the car, there is a switch activated by centrifugal force. When the car reaches a certain riding speed during driving, a device for detecting tire pressure of the car is automatically activated, so that the driver during high-speed riding is able to master the tire conditions in time to ensure driving safety. In more details, when the wheels of the car reach a preset rotation speed, the centrifugal force caused by the rotation is large enough to turn on the above-mentioned switch activated by centrifugal force and thereby to start the tire pressure detector. In this way, an automatic detection is automatically conducted.
FIG. 1A is a schematic view of a conventional switch activated by centrifugal force. Referring to FIG. 1A, an arched conductive spring strip 20 with two-stages is disposed in a switch body 10 of a conventional centrifugal switch. In normal status, the outwards-curved place of the conductive spring strip 20 with two-stages touches and props up a button 30. The top of the button 30 is protruded from the outline of the body 10 into a protrusion 31. A contact point 21 is disposed oppositely to the vertex of the arch portion of the conductive spring strip 20. The switch body 10 has a pressing rod 40 located outside the body 10, but the root portion of the pressing rod 40 is pivoted on a pivot 41 located oppositely to a side of the button 30. The body of the pressing rod 40 is tilted across the protrusion 31 of the button 30. A joining sheet 42 is disposed at the end of the pressing rod 40 and is roughly perpendicular to the body of the pressing rod 40. A thread hole 43 formed at the center of the joining sheet 42 is for connecting a weight block 50 through a bolt 51 of the weight block 50.
FIG. 1B is a schematic view showing the basic elements for detecting centrifugal force of FIG. 1A after a centrifugal force is applied thereon. Referring to FIGS. 1A and 1B, a conventional centrifugal switch is mounted on a tire or other rotating body and revolves along with the tire or the rotating body. During the revolving, the weight block 50 would drive the pressing rod 40 due to a centrifugal force, so that the pressing rod 40 swings around the pivot 41 and the body of the pressing rod 40 presses the protrusion 31 of the button 30. As a result, the button 30 contacts and presses the arched curve portion of the conductive spring strip 20. When the pressure force applied by the weight block 50 and the pressing rod 40 is increased with an increasing rotation speed to reach a preset threshold, the arched curve portion of the conductive spring strip 20 would encounter a bending instability and be sprung back into the second stage thereof. At the time, the upward arched curve portion touches the contact point 21 to turn on the switch, as shown in FIG. 1B.
Since, as the described above, the conventional centrifugal switch has on/off statuses only, so that a user is unable to obtain the information of centrifugal force in more details by means of the conventional centrifugal switch. In this regard, a novel centrifugal force sensing device needs to be developed.